Dermatology - Food Hypersensitivity

Question 1

Define adverse reaction to food.

Answer 1

an abnormal clinical response attributed to an ingested food or food product

Question 2

Define food hypersensitivity.

Answer 2

an adverse reaction with a proven immunologic basis

Question 3

Define food intolerance.

Answer 3

an adverse reaction to food that does not have a proven immunologic basis

Question 4

Define idiosyncrasy to food.

Answer 4

a qualitatively abnormal response to a food or food additive that resembles a hypersensitivity

Question 5

Define pharmacologic reactions to foods.

Answer 5

an adverse reaction as a result of a naturally derived or added chemical that produces a drug-like pharmacologic effect

Question 6

Define metabolic reactions to food.

Answer 6

an adverse reaction due ot an effect of a substance upon the metabolism of the host, or as a result of defective metabolism of a nutrient by the host

Question 7

Define food poisoning.

Answer 7

an adverse reaction to a food caused by a direct effect of a toxin

Question 8

What types of hypersensitivity reactions are associated with food allergies?

Answer 8

Type I, and possible types III and IV

Question 9

When dealing with food allergies, what must we remind clients?

Answer 9

that pets have reactions to ingredients in pet foods, not specific brands

Question 10

What are the most common dog food allergens?

Answer 10

beef, dairy products, poultry products, wheat, corn, and many others

Question 11

What are the most common cat food allergens?

Answer 11

beef, dairy products, fish, poultry products, and others

Question 12

What patients typically get food allergies?

Answer 12

Dogs and cats, often after years on the same diet

Question 13

What is specific about pruritus caused by canine food allergies?

Answer 13

It can develop at any age, it is non-seasonal, and is considered poorly responsive to glucocorticoids

Question 14

What clinical signs are associated with food allergies in cats?

Answer 14

they may show pruritus, any sign of feline ‘reaction patterns’, ulcerative lesions, or self-inflicted wounds

Question 15

What non-specific (to species) signs are associated with food allergies?

Answer 15

GI upset signs (in less than 25% of cases) and recurring pyoderma

Question 16

What are some ways to diagnose food allergies?

Answer 16

history, elimination diets, and allergy testing (but not recommended)

Question 17

What are some options for feeding trials?

Answer 17

novel protein diets or feeding hypoallergenic diets

Question 18

How do novel protein diets work?

Answer 18

animals are fed diets that contain proteins to which they have not been previously exposed to

Question 19

Homemade diets are preferred for novel protein diets, what are the preferred foods?

Answer 19

lamb and rice, fish and rice (or potato), tofu and rice (or potato), pinto beans and rice

Question 20

What about hypoallergenic diets makes them good for food allergies?

Answer 20

the proteins are hydrolyzed to reduce the size of the protein to less than 18,000 daltons to reduce antigenicity

Question 21

How long should food trials last?

Answer 21

minimum of 5 weeks, preferably 8-12 weeks in dogs

minimum of 6 weeks, preferably 8 weeks in cats

Question 22

What happens if a pet is fed something, even a table scrap, during a food trial?

Answer 22

the trial must start over at day one, pets can not be fed anything flavored

Question 23

True or false: A valid assessment is not made by changing brands of dog or cat food

Answer 23

TRUE

Question 24

What are the recommended therapies for food allergies?

Answer 24

avoidance, corticosteroids (little benefit), or adding specific causative substances

Question 25

What are the methods of avoidance in food allergy cases?

Answer 25

using homemade diets that are nutritionally complete and balance or using commercial hypoallergenic diets

Question 26

Why would you want to add specific causative substances to a pets food?

Answer 26

To identify the offending substances, then find a commercial premium food that does not have it

Question 27

What is the method of adding causative substances?

Answer 27

You add a new ingredient every 10 days and observe the patient for recurrence of lesions or pruritus